P4–270: Omega‐3 fish oil with purified eicosapentanenoic acid stimulates cerebral perfusion

Background: Omega-3 fish oil stimulates cerebral perfusion by a prostaglandinindependant mechanism as shown by animal studies. We reported at the International Conference on Alzheimer's Disease in Madrid, Spain, 2006 that acid ethyl esters of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) or Lovaza, stimulated cerebral perfusion. Owing to possibly more favorable effects of purified EPA (Vascepa) on serum lipids, not only decreasing serum triglycerides but also increasing serum highdensity lipoprotein and decreasing low density lipoprotein (LDL) vs. Lovaza which increases LDL, it is likely that Vascepa will be used increasingly. Methods: Brain SPECT used 70 MBq Tc-99m-HMPAO and a Siemens ECAM with an ultra-high resolution (5.9 mm) collimator for basal and 8 grams oral EPA-stimulated images obtained after 45 minutes. To verify the cortical metabolic index (CMi) from SPECT, a Siemens ECAT Exact 47 with 5 mm resolution and 20 MBq F-18 fludeoxyglucose (FDG). We verified a cerebral flow reserve index (FRi), the difference of a cortical perfusion index (CPi) and CMi, as a measure of cerebral perfusion in humans by comparing multiple known perfusion stimulants, including 0.8 mg sublingual nitroglycerin, 500 mg IV acetazolamide, 50 grams oral coconut oil and 10 grams oral Lovaza, all of which produce FRi (10+-2)% in near normal subjects. Results: A 57 year-old diabetic woman with minor memory complaints had CMI 59.0% by SPECT and FRi (8.4+-2.1)% when imaged fasting and normoglycemic. The regionally differential stimulant effects of purified EPA were shown in a 69 year-old traumatic brain-injured (TBI) man with mild cognitive impairment, whose CMi was (65.2+-2.2)% by FDG PET and (70.7+-3.5)% by SPECT. His post EPA FRi of (6.8+-2.7)% correlated with decreased blilateral parieto-occipital and bilateral mesial temporal perfusion tracer deficits which is not unusual in TBI patients and similar to metabolic deficits in Alzheimer's disease. Similar results were obtained with 10 grams oral Lovaza after 3 hours or 50 grams oral coconut oil after 60 to 90 minutes. Conclusion: Purified EPA omega 3 fish oil has favorable effects on serum lipids and also remarkable effects on cerebral perfusion with potential for significance in both diagnosis and therapeutics of cognitive impairment. Fig. A: Cortical Metabolic and Perfusion Index Method. Axial SPECT or PET slices acquired after tracer injection in a quiet, dark room, are parallel to the brain long axis from occipital to prefrontal. For the Corti index (CMi), one or more axial slices are centered one third of the way from the top of the brain, just superior to the roof of normal protocol used a 5 min transmission scan and a 15 min emission scan beginning no sooner that 30 min after tracer injection. Activity display is a Sokoloff color scale, with white for peak brain, black for zero and spectral colors for intermediate activities. Isocontour enclosed areas contain activity > activity. In an axial slice, a 6% isocontour represents total brain activity comparable to that seen with attenuation corrected PET and a 60% isocontour represents cortical activity, the ratio of these two 60% isocontour acti representing the fraction of total activity due to cortical activity. ^ From Blue Ash Nuclear Medicine LLC, 4743 Cornell Rd, Cincinnati, OH, 45241 USA and *The Christ Hospital, Cincinnati, OH, 45219, USA. * From MiE Germany, 112 Hauptstrasse, Seth, 23845 Germany -sized lateral ventricles. The PET image with acquisitions specified percentages of peak vity/6% isocontour activity = CMi cal Metabolic